@media screen and (min-width:1280px) {
    .container{
        /* 注意是监控container，限制container的大小 */
        width: 1280px;
    }
}
.md_nav{
    padding-left: 0;
}
.md_nav .nav{
    background-color: #eee;
    border-bottom: 1px solid #ccc;
}
.md_nav .logo{
    width: 100%;
    background-color: #337ab7;
}
.md_nav img{
    display: block;
    width: 100%; 
    margin: 0 auto;
}
.md_nav ul{
    width: 100%;
    margin: 0;
    padding: 0;
}
.md_nav li{
    width: 100%;
    font-size: 16px;
}
.md_nav a{
    display: block;
    padding-left: 30px;
    font-size: 16px;
    color: #666;
    height: 50px;
    line-height: 50px;
}
.md_nav a::before{
    padding-right: 10px;
}
.md_nav a:hover{
    background-color: #fff;
    text-decoration: none;
    color: #000;
}
.article-hd{
    height: 276px;
}
.article-bd a{
    display: block;
}
.article-bd a:hover{
    color: #000;
    text-decoration: none;
}
.pic img{
    width: 100%;
}
.article-bd li{
    border-top: 1px #c2c2c2 solid;
    margin-top: 10px;
}
.article_content{
    padding-top: 10px;
}
.pic{
    padding-top: 10px;
}
.article-hd a{
    display: block;
    height: 100%;
    width: 100%;
}
.article-hd li:first-of-type{
   float: left;
   width: 50%;
   padding-right: 10px;
}
.article-hd li:first-of-type img{
    width: 100%;
    height: 100%;
}
.article-hd li:first-of-type p{
    position: absolute;
    height: 40px;
    color: #fff;
    font-size: 20px;
    bottom: 0;
    left: 0;
    margin-bottom: 0;
    width: 100%;
    padding-right: 10px;
    line-height :40px; ;
    background-color: rgba(0,0,0,0.3);
}
.article-hd li a{
    position: relative;;
}
.article-hd li:not(.article-hd li:first-of-type){
    float: left;
    width: 25%;
    height: 128px;
    padding-right: 10px;
    margin-bottom: 10px;
}
.article-hd li:not(.article-hd li:first-of-type) img{
    width: 100%;
    height: 100%;
}
aside img{
      width: 100%;
}
@media screen and (max-width:992px) {
    /* 这里特别注意：基于bootstrap的监控机制，于屏幕992时等价于container970
    于屏幕768时，于container 750*/
    .md_nav li{
        width: 20%;
        font-size: 16px;
        float: left;
    }
    .md_nav img{
        width: 190px;
    }
}
@media screen and (max-width:768px) {
    .md_nav li{
        height: 50px;
        width: 20%;
        font-size: 16px;
        float: left;
    }
    .md_nav img{
       width: 90px;
       
    }
    .article-hd li:first-of-type{
        float: left;
        width: 100%;
        height: 266px;
        padding-right: 10px;
     }
     .article-hd li:not(.article-hd li:first-of-type){
        float: left;
        width: 50%;
        height: 128px;
        padding-right: 10px;
        margin-bottom: 10px;
    }
}
